An air conditioning circuit of a motor vehicle for example is a closed circuit which comprises several elements, in particular a compressor, a condenser, a desiccant reservoir, an expansion system, an evaporator and sometimes a pipe, in which elements flows a refrigerating fluid. All of these elements of the air conditioning circuit are connected by rigid and/or flexible pipes which have near each of their two ends a fixing and connecting system.
Furthermore, the whole air conditioning circuit also comprises pressure and/or temperature sensors which are connected to a control unit for managing the functioning of the air conditioning circuit. At present, the fitting of a sensor is carried out by tapping into one of the constituent elements of the circuit, most often in a rigid pipe of the circuit, which necessitates drilling a hole in the element, which is most often made of aluminum, in order to engage in it one end of a rigid support of the sensor.
The fixing of this support, generally made of aluminum, is carried out by a brazing operation which is difficult to carry out because it must be perfectly fluid-tight over the whole of the periphery of the hole drilled in the element of the hydraulic circuit in which it has been fixed.